Effects of Micro-Arc Oxidation of Ti6Al4V Alloy on Adhesion Property to Electroless Ni-P-ZrO2 Composite Platings and Their Wear Resistance

摘要:

在Ti6Al4V合金微弧氧化膜表面制备Ni-P-ZrO2化学复合镀层，微弧氧化处理时间分别为15、30、60、90 min。采用扫描电镜/能谱仪、划痕试验、热震试验、显微硬度计和球盘式摩擦磨损试验机研究了微弧氧化膜结构对Ni-P-ZrO2化学复合镀层的结合性能与摩擦性能的影响。结果表明：随着微弧氧化时间的增加，复合镀层的结合性能显著提高，原因是微弧氧化膜的多孔性结构及其机械锁合效应。与Ti6Al4V合金相比，微弧氧化+化学复合镀处理后的试样硬度和耐磨性显著提高，Ti6Al4V合金表现为是严重的黏着磨损，而Ni-P-ZrO2复合镀层以磨砺磨损为主

Abstract:

An electroless Ni-P-ZrO2 composite plating was prepared on the porous surface of the Ti6Al4V alloy pretreated by micro-arc oxidation (MAO) for 15, 30, 60 and 90 min, respectively. The effects of the microstructures of the MAO coatings on the adhesion properties of the electroless Ni-P-ZrO2 plating and their tribological behavior were examined by SEM/EDS, scratch and thermal shocking tests, a microhardness tester and a ball-on-disc wear testing machine. The results indicate that the adhesion property of the Ni-P-ZrO2 composite plating of the MAO coatings is distinctively improved with the increase of MAO processing time. The reason is attributed to the larger porosity and the enhanced mechanical interlocking effect. Compared with the Ti6Al4V alloy, the microhardness and the wear resistance under drying sliding condition of the Ti6Al4V alloy are greatly improved by the duplex treatments. The wear mechanism of the Ti6Al4V alloy is severe adhesion and abrasion wear, while the electroless Ni-P-ZrO2 composite plating shows microabrasion wear.